1. Field of the Invention
The present invention relates to a UCOL-type star network for the optimal management of various kinds of traffic and more particularly to a UCOL-type star network having a central unit or passive star center and a plurality of depending stations connected via two-way optical fiber channels, with said stations communicating through an access protocol having a frame structure.
2. Description of the Prior Art
As it is known, in the art of communications management in a network, where there are several transmitting stations, it is important to determine the access priorities of each station to the network itself, and then to the resources thereof, so as to avoid collision between the information packets generated by the various stations.
Relative to ultra-wide coherent optical local networks, hereinafter UCOL networks, such a problem is particularly prominent due to their particular characteristics concerning topology, technical features and types of offered services.
A typical UCOL network is configured as a passive star where each station is connected with its star center via two dedicated optical fibres. One fibre serves for transmission from the station to the star center and the other one for reception.
Each optical fibre is capable of to a multiple transmission channel.
The particular kind of optical fibre link using the coherent optics technology, allows that different channels be multiplexed through frequency division and used for several transmissions along the same fibre, thus optimizing the link resources.
As concerns the management of the access of each station to the network, the known access protocols do not fit the needs for effective management of access by each station with a UCOL network. Moreover, although access protocol systems using a priority concept are already available, at the present state of the art they appear to be intrinsically very complicated as to frame structure. For such reason they cannot satisfy the functional characteristics of a UCOL network and cannot optimize the resources therein contained.
This is due to the fact that the trend of the ideal management of access disputes to network resources, during the transmission of the various data coming from the various stations, is not well defined in the prior art.